Cancelling EUSS permit application

[NatCam]

Hello everyone,
I need to cancel EUSS family permit application and start a new one.
How do I cancel it? It doesn't seem to be possible. All the links are useless.
I need to book a new appointment with TLS. It looks like one can't do this, unless new application has been submitted. In short, I need to start new application in order to book another appointment.
TLS website is just horrible.

[Kingsaab777]

Leave it that just start new one..dont worry about cancel

[NatCam]

Leave it that just start new one..dont worry about cancel

Thank you.
The problem is my sister has already attended the appointment at TLS centre in Athens. For technical reasons, I was too late to upload her documents and she left without giving biometrics.
Now, documents have been uploaded and submitted, but it isn't possible to book another appointment for biometrics only.((
Are you sure we can dismiss the previous one?
Okay, I shall follow your advice. Thanks again.
(I'm doing the application on my sister's behalf, since she has no means to do it herself.)